Guard apparatus for the needles of knitting machines



March 16, 1954 I WOLF 2,672,036

GUARD APPARATUS FOR THE NEEDLES OF KNITTING MACHINES Filed July 24, 19512 Sheets-Sheet 1 20 28 e k I 36 LL 2 35 INVENTOI? ARTHUR MJMOLF y- A /r1I 1 ATTORNEYS M h 16, 1954 I A. M. WOLF 2,672,036

GUARD APPARATUS FOR THE NEEDLES OF KNITTING MACHINES 2 Sheets-Sheet 2Filed July 24, 1951 INVENTOR 6 ARTHUR M. WOLF A Tram/Eva Patented Mar.16, 1954 GUARD APPARATUS FOR THE NEEDLES F KNITTING MACHINES ArthurMoritz Wolf, Coogee, near Sydney,

New South ,Wales, Australia Application'July 24, 1951, Serial No.238,239

. 1 This invention'relates to guard apparatus for the needles ofknitting machines to prevent the fabric pressing-off the needles. Theinvention particularly refers to machines of the circular rib andjacquard types. V

In knitting machines of the circular rib'and jacquard types the fabricoften presses-off the needles due to various causes, but most commonlydue to fiufi and the like obstructing a yarn guiding hole or the feedinghole in a yarn carrier, and also due to faulty wound yarn and the like.The above-mentioned occurrences willnaturally stop a thread from feedinginto the machine, and it is often beyond the control of the existingstop motions to stop-a machine in time to prevent the press-off of thefabric. The other unobstructed threads will keep on feeding and lumpingup yarn onto the needles often breaking the latter, until the needledetector stops the machine. The fabric must then be picked up onto theneedles again. The above enumerated disabilities'cause much loss oftime, reduction in production, and also waste of yarn and needles. Inthe case of jacquard machines with bird'seye back, the fabric does notalways run-off the needles but is rendered defective in quality andbecomes useless.

The-present invention has been specially devised to provide simple andinexpensive guard apparatus whereby the above mentioned disabilities areeliminated, thereby saving yarn, needles,time and temper, with increasein production, and wherein the fabric has clean and even stitches. Also,the use of the invention enables the running speed of the machines to beincreased by at least per centum, as the general mechanical constructionof most machines will permit of such an increase. Furthermore, theapparatus is safe from electric shock, and the circuit thereoffoolproof.

According to this invention, the guard apparatus for the needles ofknitting machines of the type hereinbefore mentioned consists broadl'yof an electro-mechanical device formed as a complete unit having afinger member slidably mounted from the said device in such a manner as'to contact the fabric being knitted as it passes throughthe openingbetween the dial and cylinder of the machine, and the fabric exerts apressure effect on the said finger member. The other end of the saidfinger member operatively connects with contact elements and associatedelements of the device-arranged to instantly interrupt or make an'electric circuit of a relay controlling the operationof the machine. The

7 Claims.. (01.?66-166) arrangement is such that when a pressure efiectis exerted on the finger member by the fabric in its normal movementfrom the knitting needles, the contact elements and associated elementsof the device break the circuit, but immediately the pressure effect onthe finger member relaxes, due to the fact that the fabric is no longermoving from the knitting needles, the circuit of the relay switch ismade, and the machine immediately stopped. The resulting break in-thefabric is only comparatively small, usually about four inches. 1

These knitting guards in the fitting maybe screwed onto thedial-cam-boxes say by screws or attached in other manner. On somemachines it may be desirable to screw the knitting guardsonto thecylinder-cam-boxes, depending on the construction of a machine. The baseplate is modified in such a case to suit the machine. The position ofthe finger member of each unit-is immediately after the needles havepassed a yarn carrier, that is, after the stitches have been formed andall the needles are well back in the dial and cylinder.

The electric circuit of the guard and the relay is a lowvoltage one,'say from 4 to 12 volts, supplied from a battery or preferably atransformeris used to operate the relay switch for stopping the machine.

Any other stop motions, such as top stop motion, chain control and thelike, may be connected to the circuit by simple contact switches.

With this invention the pin of the old needle detector is eliminated,although the lever of the relay switch may be used in connection withsuch needle detector or part thereof to effect the stopping of themachine.

In order to describe the invention more fully reference will now be madeto the drawings accompanying and forming part of this completespecification wherein:

Figure 1 is a sectional elevation of portion of the dial and cylinder ofa knitting machine and the present'guard apparatus showing the lattermounted upon the said dial, and in which ma chine the cylinder and dialrotate in a clockwise direction.

Figure 2 is a perspective view of portion of the dial and cylinder inFigure 1 showing the guard apparatus in use in association with knittedfabric formed by the knitting machine.

"Figure 3 is a perspective view of the guard,

apparatus with its cover removed.

Figure 4 is a face view of a form of the finger.

member in the apparatus.

Figure 5 is an alternative form of the finger member illustrated by aperspective view.

Figure 5A is a vertical section taken along the line AA in Figure 5.

Figure 6 is a perspective view of clutch releasing means and trip relaywhich is operated by the guard apparatus.

Figure 7 is a. detail view in section of the trip lever which isoperated by the trip relay for the purpose of stopping the knittingmachine.

Figure 8 is an elevation of the trip relay casing with its cover removedto illustrate the various parts of the relay within.

The guard apparatus consists of a base 9 fixed as by screws to thedial-cam-box: plate. t: situ:= ated above the knitting machine dial i iin which the horizontally disposed knitting needles. l2 are. housed asseen in Figures 1 and 2. This base 9 overhangs the dial-cam-box H! byits end. i3,.to which is fitted a rocking lever I4 pivotally mounted. ona holder l5.

Qne end or the rocking. lever 14 carries a. con.- tact; Hi and inwardlyof which there is formed av slot. M... through which there passes in afree man-.

nor a. threaded. red It screwed into the base 9. and i 23. are mountedupon an. insulating block 31 355 aiiixed to the base 9.

Associated with the outer end 24 of the rock ing lever [4 there is a.finger member which is slidably fitted. in an angularly set guide 26which is: conveniently formed from a projection of the.

end it of they base plate 9. This finger member- 2 is provided with anotch 2? to prevent its s lodgment irom the guide 26 through. theengagement of an arm 28 with the shoulders oi such. notch 2'! as shownin Figure 4.

Alternatively this finger member 2., may be provided with a slot. 29 (asseen, in Figure 5) in.- which. shoulderedl screws 3c are fitted. to;allow; limited slidable movement of the said finger 25,. such screws 39being fitted into. an angled extension at of, the end 53. of the base 9.

The lower: end of the slidable finger is formed. with. a curvedfoot-like protection 32 which is adapted to. ride upon the knitted.fabric 33 formed. by the needlesof the knitting machine.

When the machine is working normally, the: foot 32 rides upon the fabric33 and maintains: the arm L4 approximately midway between the contacts22 and- 2-3, as shown in Figure; 1 When; breakage of. the feed. thread34 occurs, the fabric. 33 looses its tension and allows the foot 32 to.-sink, thus causing the rocking lever M to drop at its. end 24 elevating;its contact l6 and causing; to make.- contaot with the upper contact;-element. 22.. Should there be. defective needles among, the needles 1-2.in the. dial ti or the. similar needles 35 in the cylinder 36 of theknittingma chine, the. foot 32-. is forcedupwardly thus causing therocking arm Hi to; make contact through its. contact end is with the,lower contact; element 23.

The operation of the contact, [6 on the, rocking lever l4 contactingwith either of the. con-- tact. elements 22. or 2.3. closes an electric.circuit from a transformer 38. which causes a.lo.w voltage current toflow through the wire 39 then to either of the contacts 22 and 23 to therocking lever l4 and through the base 9 to the earth connection 40 tothe frame of the knitting machine (see Figure 3).

fhe electric circuit is then completed through the machine earthconnection 4| (see Figure 8) and the: electromagnet coil 42 of the triprelay 43 and finally to a wire 44 which leads to the transformer 33.

When the coil 42 is energised the magnet 45 attracts. an armature 46which releases the end A]: of a. lever 4t, which swings about a pivot 49through the energy of a tension spring 50. This releasing. movement ofthe end 41 of the lever 43 opens the circuit through the magnet coil 42by means of a contact Ha which moves away from a contact spring Albwhich is mounted upon an insulating block 410.

The other end iii of the lever 48 forces an arm 52. out of engagementwith a. notch 53 of. a. resetting. rod. 5 2 which moves downwardlythrough the energy of the spring 55: to. depress an arm 55 on a shaft5'5- to the other end of which a notched arm 58 is raised to release a.pin 59 on a. pivoted spring controlled resetting arm 69. as shown. inFigures 6 and '7.

The arm 6.0 now moves by the. energy of a spring 6 l. to draw theslidable cone 62 away from the fingers 63 which are part oi an expandingclutch of which there are: many well. known types.

The shaft 64 carries a pulley at each end one of which is associated,with the clutch andis driven by a motor or the like. andthe other pulley is. adapted to drive. the knitting machine.

It is to be understood that. although one type. of trip. mechanism hasbeen described and. illustrated, there are many other known forms oftrip mechanisms. fitted. to the various types of. knitting machines, towhich the present invention. may be adapted, and its application. is notlimited, to the. above described example of relay and clutch releasingmeans.

invention is also easily adapted to. op-

I crate different known designs of trip mechanisms fitted to the variousmachines which em. ploy a belt shifting device to move the driving beltfrom. the. fast to. the loose pulley for stop-- ping or starting. the.machine.

The number of devices. used with. each 'machine is governed by the.number of feeds of the. machine usually ranging. from 4 to. 12 feeds.and there is one of the devices for each feed.

The range of circular knitting machines in regard to their constructionis very large therefore the knitting guard described hereinv may have tobe modified to suit. the various machines. It has been found byexperience. that about three models for each direction. of knitting,that.

' is clockwise, or antil-clockwise, should cover the total, that isfull. range. of machines. Brovision can be. made to allow for. theraising or lowering of the dial to alter the tension of the knitted.fabric.

This knitting guard. can be adapted also for use in open machines whichdo the knitting. on a cylinder only. These machines are; commonlyknown.as; jersey machines- I claim:

L. An improved. guard apparatus; for the knitting needles of knitting,machines; of. the circular rib and jacquard types having a dial housinghorizontally disposed knitting need-1es, a; (115311-- cam-box,. acylinder housing vertically. disposed;

needles, a shaft for driving said machine, and a clutch releasingmechanism operatively connected to said shaft, the horizontal andvertical needles being arranged to knit a fabric, the knit fabricpassing through the opening of the dial and cylinder, said guardapparatus comprising an electro-mechanical device formed as a completeunit and including a finger member slidably mounted within the devicewith one end in contact with the fabric being knitted as it passesthrough said opening, whereby the fabric exerts a pressure effect onsaid finger member, a relay switch having a suitable electrical circuitfor controlling the operation of said machine through said clutchreleasing mechanism, and means for establishing contact between saidfinger member and the electrical circuit of said relay switch, saidfinger member being operatively connected to said contact means and saidcontact means being arranged to instantly interrupt or complete saidelectrical circuit, said electro-mechanical device being arranged sothat the pressure effect exerted on said finger member by the fabric inits normal movement from the knitting needles holds the said contactmeans in a position which breaks the circuit of the relay switch, butwhen the pressure effect on the said finger member relaxes since thefabric is no longer moving from the knitting needles, the electricalcircuit is completed and the machine immediately stopped-throughactuation of said relay switch which in turn actuates the clutch releasmechanism operatively connected to the drive shaft of the machine.

2. A guard apparatus as defined in claim 1, in which the saidelectro-mechanical device includes a base securable to the dial-cam-box,and

means at one end of said base for slidably mounting the finger member,and in which said contact means includes a lever arm rockably mounted onsaid base so that one of its ends rests against the upper end of thesaid finger member, a contact member carried at the other end of saidrockable lever arm, said lever arm being in electrical connection withone side of said electric circuit, and a pair of spaced contacts, onebeing located on either side of said lever contact member so as to makecontact with same on upward or downward movement thereof, said contactsbeing insulated from said base 7 and being connected to the other sideof the circuit of the said relay switch.

3. Improved guard apparatus according to claim 2, wherein the rockablelever arm has an extension at one end to contact the top of the fingermember and is pivotally mounted to a bracket on the base inwardly ofsaid extension, said base having an upwardly extending rod fixedthereto, and said lever arm having a longitudinally extending slot, saidrod extending through saidslot, a coiled spring being sleeved on saidrod and bearing against said lever arm to normally elevate the endthereof carrying the contact thereon.

4. Improved guard apparatus according to claim 2, wherein the saidspaced apart contacts extend from a common insulating block secured tothe base, one contact overlying the contact member carried by the leverarm on the upper side and the other underlying said contact memher.

5. Improved guard apparatus according to claim 2, wherein the fingermember is of barlike form having a foot at its lower end which issuitably shaped for riding upon the knitted fabric formed by the needlesof the knitting machine, while its top end is suitably shaped forcontacting the end of the rockable lever arm, and wherein said fingermember is slidably mounted by a bracket fixed to said base.

6. Improved guard apparatus according to claim 5, wherein said bracketwhich slidably mounts the finger member is a guide which projects fromthe end of the base, in which a slot is formed in the side of saidfinger member adjacent its upper end, and in which a projectionextending from the said base engages in said slot in a freely slidablemanner to prevent the dislodgment of said member from said guide.

7. Improved guard apparatus according to claim 5, wherein the fingermember is provided with a slot extending longitudinally therealong, andis slidably mounted on said bracket fixed to the base by at least oneshouldered element having a shank which passes through saidlongitudinally extending slot and is secured in the said bracket.

ARTHUR MORITZ WOLF.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,036,243 Wachsman Apr. '7, 1936 2,362,783 Vossen Nov. 14,1944

